If you want to see a screenshot, follow the link. (Had to manipulate it because the forum denied my post otherwise... That's strange)
_HTTP_burngine_DOT_bplaced_DOT_com/stuff/img/vsm-error-close-distances.png

The light comes from above. As you see, just under the green "leaves" the shadow is that weak, that you can't really see it. Only with more distance the shadow becomes really visible.